1. Field of the Invention
The present invention concerns a novel periplanone-B analogue used as biologically active material, in particular, as attractant for cockroaches, etc.
2. Description of the Prior Art
Cockroaches are typical insanitary and unpleasant pests which invade in various industrial places as well as domestic houses to give great damages. In view of the above, although various controlling methods have been used, use of insecticides suffer from restrictions since their habitats are closely related with human livings. In addition, effective control can not be obtained by conventional insect trapping means since cockroaches have a habit of hiding themselves in narrow gaps, etc. and have a strong reproducibility and they would be repeat infestation even after control.
In recent years, studies have been developed for pheromones of cockroaches and the study for using them to the control of cockroaches has been started. Pheromones are chemical substances secreted from insects for the preservation of species and it has been known that pheromones show potent activity such as attraction even in a very minute amount. Accordingly, it is considered that a pheromone can provide effective and non-toxic novel control means if it is used as an attractant for insect catching means.
By the way, periplanone-B is a compound having the structure represented by the following formula (B): ##STR1## which is a major component of a sex pheromone secreted from female American cockroach (Periplaneta americana), which attracts male cockroaches to cause sexual excitation even in a amount of 10.sup.-6 -10.sup.-7 .mu.g. The compound (B) was isolated and determined for the structure by Persoons, et al. (C. J. Persoons, et al., Tetrahedron Letters, 24, 2055 (1976)) and its stereochemistry was determined by Still, Nakanishi, et al (W. C. Still, J. Am. Chem. Soc., 101, 2493 (1979); K. Nakanishi, et al., J. Am. Chem. So., 101, 2495 (1979)).
The synthesizing process has been reported, in addition to the Still's method as described above, also by Schreiber, et al (S. L. Schreiber, et al., J. Am. Chem. Soc., 106, 4038 (1984)), Hauptmann, et al. (Hauptmann, et al., 27, 1315 (1986)), Kitahara, et al. (T. Kitahara, et al., Tetrahedron Lett., 27, 1343 (1986)), Takahashi, et al (T. Takahashi, et al., J. Org. Chem., 51, 3394 (1986)), De Clercq, et al., (P. J. De Clercq, et al., Tetrahedron Lett., 29, 6501 (1988)).
In addition, a minor pheromone component, periplanone-A is also known (C. J. Persoons, et al., J. Chem. Ecol., 5, 22 (1979); H. Hauptmann, et al., Tetrahedron Lett., 27, 6189 (1986)), and the structure has recently been determined (M. Mori, et al., J. Chem. Soc. Perkin Trans, 1, 1769 (1990)).
Other kinds of substances having sexual pheromone activity much weaker than that of natural pheromones, which are known as mimics, have also been found and there are known bornyl acetate (W. S. Bowers, et al., Nature, 232, 259 (1971)), germacrene-D (S. Takahashi, et al., Agric. Biol. Chem., 39, 1517 (1975)), verbenyl ester, verbanyl ester (C. Nishino, et al., Appl. Entomol. Zool., 12, 287 (1977)).
For applying the known pheromones and mimics as described above to the control of American cockroach (Periplaneta americana) there are the following problems.
Periplanone-B can be obtained only by 0.2 mg even when collected from 75,000 cockroaches and it is impossible to use extractants from insects as an attractant. Accordingly, it is necessary for the mass production by an organic synthesis process.
However, there are the following difficulties:
(1) Synthesis for 10-membered carbon rings as the fundamental skelton is difficult, for which no practical production process has yet been established, PA1 (2) Since the compound has many asymmetric carbon atoms and its stereoisomers show no activity, it requires a highly skillfull stereo-controlling method in view of synthesis. PA1 (3) Since the compound has an unstable structure such as epoxy group or diene in the molecule, it is easily decomposed, PA1 (4) Since existent synthetic processes require lengthy production steps because many functional groups have to be introduced in a stereoselective manner and many reactions such as organic metal reactions or cyclizing reactions requiring accurate condition settings are used, they are not practical.
In addition, since known pheromonally active substances (mimics), even powerful ones, have activity only to 1/1,000,000 of natural products, they have even not yet been put to practical use at present.